Derivative of pinene and process of producing same.



UNITED frnrns ATE-NT union.

NATHANIEL THURLOW, OF NIAGARA FALLS, NEW YORK, ASSIGNOR,BY MESNEASSIGNMENTS, TO THE PORTCHESTER CHEMICAL COMPANY,

A CORPORATION OF NEW YORK.

DERIVATIVE OF PlNENE AND PROCESS OF PRODUCING SAME.

SPECIFICATION forming part of Letters Patent No. 726,783, dated April28, 1903.

Application filed December 11,1901. Serial No. 85,425. (31190111191159T0 at whom it may concern.-

Be it known that I, NATHANIEL THURLOW, a citizen of the United States,residing at Niagara Falls, in the county of- Niagara and State of NewYork, have invented certain new and useful Improvements in Derivativesof Pinene and Processes of Producing Same, of which the following is aspecification.

This invention relates to improvements in the production of derivativesof pinene and also to certain of such derivatives as new products. In myLetters Patent No. 698,761, dated April 29, 1902, I have disclosed aprocess of making camphor by the action of oxalic acid on turpentine,(pinene,) and in carrying out this process it was found that a number ofintermediate products were formednamely, pinyl oxalate, pinyl formate,borneol oxalate, borneol formate, and polymerization prodnets of pinene.All these products may be regarded as derivatives of pinene, either bysubstitution, addition, or polymerization. In my said application theprocess of forming camphor in this manner was claimed, and claim wasalso made to one of the intermediate productsnamely, pinyl formate.

The present application relates to certain matters disclosed but notclaimed in said application and relates,further,toa feature of theprocess not specifically described thereinnamely, the production ofdipentene. When the pinene is heated with the oxalic acid, a large partof it is polymerized, forming, mainly, dipentene, and in the subsequentdistillation this substance passes over first. Dipentene being initselfa commercial article having recognized uses, I arrange to collect thisportion of the distillate separately.

The product of the action of oxalic acid on turpentine is a complex oilymass, which constitutes a new product suitable for sale as such and maybe used in the manufacture of any or all of its components orderivatives such as pinyl oxalate, pinyl formate, borneol oxalate andformate, camphor, or dipentene and the present invention relates also tosuch mass.

Three hundred and fifty pounds of rectifiedand dehydrated turpentine areheated with about seventy pounds of anhydrous oxalic acid to atemperature preferably of from 120 to 130 centigrade, although a lowertemperature may be used. If a large percentage of oxalate and formate bedesired, a low temperature should be used. When the reaction ceases, theresulting oily product contains about two hundred pounds of dipentene,about six per cent. of pinyl formate, about three per cent. of pinyloxalate, and the remainder consists of free camphor, borneol oxalate andformate, and the higher polymerization products of pinene, with more orless free acid. The next step of the process is to wash the mass withwater to remove this free acid. The resultant complex oil may be storedand sold in that condition and serve as a basis for the production ofthe other products. The specific gravity of this oil is about .902 andboiling-point 185 centigrade. The subsequent treatment may depend on theproduct which is desired. If oil containing as high a percentage aspossible of pinyl oxalate and formate is desired, the oil is distilledat a low temperature and pressure, (78 to 82 centigrade and vacuum ofone-half atmosphere.) By successive distillations in this manner thepinyl formate may be increased in the residue or non-distilling portionto about forty-five per cent. and the oxalate to about seven per cent.,the rest of the resulting oily liquid being mainly polyterpenes andborneol formate. The distillate consists, mainly, of dipentene, withsome borneol oxalate and formate.

For the production of dipentene the oil must be distilled and thedistillate collected. The distillation above referred to for theincreasing of the pinyl formate and oxalate results also in theproduction of an impure dipentene as a distillate. The production ofthis dipentene is, however, advantageously carried on in connection withthe production of camphor from the complex oil, and the operation wouldthen be as follows: Enough alkali is added to the oil to saponify allthe borneol oxalate and formate present and the mixture then distilled.The borneol oxalate and formats are decomposed, yielding free borneoland a formate or oxalate of the alkali metal, (caustic soda, lime, orbaryta.) The first portions of the distillate consists mainly ofdipentene, which is separately collected. The later portions of thedistillate contain camphorand borneol,mixed with considerablehigh-boiling oils. The residue in the still consists of alkalisalts,with some nonvolatile oil. It will be understood that in thisheating the pinyl oxalate and formate become broken up, forming camphorand borneol. The first part of the distillate, consisting mainly ofdipentene, may be collected and sold as such. The camphor and borneol inthe later portion of the distillate are separated from the oily mattertherein by freezing, centrifugaling, and washing, with cold water, andthe product then treated with the proper amount of potassium bichromateand sulfuric acid to oxidize the borneol to camphor. The resultingcamphor is then centrifugaled, washed, dried, and sublimed with lime.

The compound pinyl oxalate described herein and the process of makingthe same are not claimed in this application, but are claimed in myapplication, Serial No. 118,432, filed August 5, 1902.

Having thus described my invention, the

following is what I claim as new therein and desire to secure by LettersPatent:

1. The process of producing dipentene which consists in heatinganhydrous turpentine with anhydrous oxalic acid, distilling theresulting product and collecting the distillate containing dipentene.

2. The process which consists in heating anhydrous turpentine withanhydrous oxalic acid,washing the product with Water to re-. move acid,and then distilling and collecting the first portion of the distillate.

3. The process which consists in heating anhydrous turpentine withanhydrous oxalic acid, adding alkali to the resulting product tosaponify the ethereal salts present, distilling and separatelycollecting the first part of the distillate containing dipentene and thelater parts containing camphor and borneol.

4:. The-product consisting of a complex oil containing dipentene, pinyloxalate, pinyl formate, borneol oxalate, borneol formate and camphorsubstantially as described, said oil having a boiling-point of about 185centigrade, a specific gravity of about .902.

NATHANIEL THURLOXV.

Witnesses H. O. ROLLER, CHARLES WELLES Corr.

